Massage chair

Abstract

A massage unit of a massage device moves upward and downward along a backrest of a chair. A pair of therapeutic arms are pivotably supported on a pair of pivot arms projecting forward when viewed from the backrest. Therapeutic fingers on the therapeutic arms have massage balls disposed on them. The pivot arms are driven to move the therapeutic arms in three dimensions, i.e., up and down, left and right, forward and back, so that a patient is massaged by the massage balls. An angle detector detects the angle of the therapeutic arms relative to the pivot arms. The magnitude and change in the output of the detector is used to determine the portion of the patient's body that is being contacted by the massage balls at any time.

What is claimed is:  
     
       1. A massage chair comprising: 
       a backrest on said chair;  
       a massage unit associated with said backrest;  
       means for permitting raising and lowered said massage unit along said backrest;  
       first and second therapeutic arms pivotably supported on first and second pivot arms, respectively, projecting forward from said backrest;  
       therapeutic fingers on said therapeutic arms;  
       massage balls on said therapeutic fingers;  
       means for driving said pivot arms in three dimensions to massage a patient with said massage balls; and  
       angle detecting means for detecting an angle of said therapeutic arms relative to said pivot arms.  
     
     
       2. A massage chair according to  claim 1  wherein said angle detecting means includes: 
       a coil disposed on one of said therapeutic arm and said pivot arm;  
       a magnetic core disposed on the other of said therapeutic arm and said pivot arm;  
       said core being moved into and out of said coil by a change in said angle.  
     
     
       3. A massage chair according to  claim 2  wherein said coil is a cylinder and said magnetic core moves in said coil in a reciprocating manner. 
     
     
       4. A massage chair according to  claim 1  further comprising: 
       a detection circuit;  
       said detection circuit including means for detecting a massage position on a body of a patient on which a massage operation is taking place; and  
       said detection circuit being responsive to a position at which said massage balls contact said patient based on an angle change of said therapeutic arms relative to said pivot arms detected by said angle detecting means.  
     
     
       5. A massage chair according to  claim 4  wherein said angle detecting means includes: 
       a coil disposed on one of said therapeutic arm and said pivot arm;  
       a magnetic core disposed on the other of said therapeutic arm and said pivot arm;  
       said core being moved into and out of said coil by a change in said angle.  
     
     
       6. A massage chair according to  claim 5  wherein said detection circuit produces a voltage having an amplitude related to an inductance of said coil. 
     
     
       7. A massage chair according to  claim 6  further comprising means for detecting a massage position at which said massage balls contact said patient. 
     
     
       8. A massage chair according to  claim 7  wherein said means for detecting a massage position includes means for responding to a maximum value of a voltage waveform to detect a massage position at which said massage balls comes into contact with said patient. 
     
     
       9. A massage chair according to  claim 6  wherein said detection circuit includes means for responding to an average value of a voltage waveform to detect a massage position at which said massage balls comes into contact with said patient. 
     
     
       10. A massage chair according to  claim 6  wherein said detection circuit includes means for responding to a degree of uniformity of a voltage waveform to detect a massage position at which said massage balls comes into contact with said patient. 
     
     
       11. A massage chair according to  claim 6  wherein; 
       said detection circuit detects data comprising at least two of a maximum value, an average value, and a degree of uniformity of a voltage waveform; and  
       said means for determining a massage position at which said massage balls comes into contact with said patient based on said data detected by said detection circuit.  
     
     
       12. A massage chair comprising: 
       a backrest;  
       a massage unit in said backrest;  
       means for raising and lowering said massage unit in said backrest;  
       a pair of therapeutic arms on said massage unit projecting forward therefrom;  
       therapeutic fingers on said therapeutic arms;  
       massage balls on said therapeutic fingers;  
       means for moving said therapeutic arms in three dimensions whereby a patient receives a massage from said massage balls;  
       one of a coil of wire and a magnetic core disposed on said therapeutic arm;  
       the other of said coil of wire and said magnetic core being mounted on an element of said massage unit;  
       said coil and core being positioned so that said core moves in and out of said coil in response to a change in an angle between said therapeutic arm and said element; and  
       angle detecting means for detecting said change in the angle between said therapeutic arm and said element.  
     
     
       13. A massage chair according to  claim 12  wherein said coil is a cylinder and said magnetic core moves in said coil in a reciprocating manner.